Water-heater construction.



F. L". 0. WADSWORTH.

WATER HEATER CONSTRUCTION.

APPLlcATlox man Vocr. 3. 191|.

1,248,958. Patented De@. 4,1917.

5 SHEETS-SHEET l.

F. L. o. wAnswonTHl WATER Henin cousnucnou. APPLICATION FILEP 06123.191|.

1,248,958. Pgnd De@ 4, A1917.

s sains-suur 4.

. F. L. 0. WADSWORTH.

WATERJMEATER CONSTRUCTION. nrru'lcnron msn ocT. a, 1911.

Fg. /l 24' 2H I Y f5 f 1 I/ ses ' wnntsszs? Patented D00. 4, 1917.

INVINTOR Leashes.

vUNITED STATES PATENT orrioE.

FRANK L. 0. WADSWORTH. 0F SEWICKLEY, PENNSYLVANIA..

'To alla) hom it may concern.

Be it known that I, FRANK L. O. WADs- WORTH, acitizen of the UnitedStates, residino' at Sewickley, in the county of Allegheny an State ofPennsylvania, have invented certain new and useful Improvements in.Tater-Heater Constructionsof which the trolled from the thermostat morepositiv-ely than in apparatus of this general character as heretoforeConstructed; the provision of an apparatus of the character specifiedwherein `the operation of the wateractuated member is'` controlledthermostatically by reversing the water pressure upon such wateractuated member; and in general, the f.

provision of a simplified and reliable mechanism for controlling thesupply of fuel to the burners by the water pressure and by thetemperature of the water in the heater. Certain embodiments of theinvention are illustrated in the accompanying drawings, wherein Figuresl to 4 inclusive are diagrammatic views indicating in various formsthegeneral/principle of operation of the apparatus; Figs. 5 and 6v arefront and side elevations respectively of a water heater equipped withone form of my controlling mechanism; Fig. 7 is a section through theform of controlling mechanism shown in Figs. 5 and 6; Fig. 8 is a`section through a modified form of controlling mechanism capable of usein lace of the mechanism shown in Fig. 7 Fig. 9 is a section through-another modifiedform of controlling mechanism;

' Fig. 10 is a-section through another modified form of controllingmechanism; and Fig. ll-is'a section through still another type ofcontrolling mechanism.

ABriefly Vstated the mechanism in all its various forms consists in awater actuated member, generell -a piston or diaphragm, whose oppositesi es are exposed tordiiferent pressureswhen the outlet from the heater1s opened, together with a therlnostatically controlled means orvalve s6arranged that' S'pecication of Letters Patent.

WATER-HEATER CONSTRUCTION.

Application led October 3, 1911. Serial No. 652,577.

when the temperature of thc water rises above a predetermined. point,the water pressure on the two Sides of the water actueted member isreversed. The water actuated member is arranged so as to open the gasvalve when the heater outlet yisV opened, and permit the closing of suchvalve when the thermostat cntrolling means causes a reversal. of thewater pressure on the water actuated member, and thus. produces areverse movement thereof.

The diagrams of Figsl to ilcare intended to give a general idea of theprinciple of.

operation of my apparatus divorced from the detail mechanism in whichthe invention is preferably embodied. such detail mechanism being shownin Figs. T to 1l. In the various diagrams A indicates the position ofthe parts of the apparatus when the temperature of the water is below apredetermined point and no water is being drawn from the heater, Bindicates the position .of the parts ot the apparatus when the outletfrom the heater is open; and C the position of the parts of theapparatus when the outlet is open and the temperature of the water risesabove a predetermined. point, at which time the thermostat causes areversal of pressure on the water actuated member.

In the diagrammatic illustrations' of Fig. l, the cold water enters theapparatus at the opening l and is directed to one end or the other ofthecylindcr .3 by means of the water directingl valve' B, the positionof which is4 controlled by any suitable form of thermostat connected 'tothe stem 4. 'In the cylinder 2 is located the water actuated mem er 5which is 'connected to thc stem 6 and by its movement serves to actua'tethe gas valve 7. The water passes away from the cylinder 2 throng-Iranopening.;` S connected to the heating receptacle. A spring 9 serves tokeep the water actuated member 5 in the normal left hand position showninV hand port to the valve 3, forces the piston to the right, thusclosing the gas valve 7 ,A and thus ,asses out through the opening 8 tothe hea er. Y

In the diagrammatic illustrations of Fig. 2, the thermostatieallycontrolled valve 3 is placed 0,11 the .outlet side of the cylinder l n nl A n the valve 3 is in the position shown in dia- 2', the Waterentering this cylinder through the opening 1, and moving the piston o totheyleft-opening the 'gas valve--when grain B, and movin the said pistonto the right-thus closing the gas valve-when the thermostatbrings thevalve 3 to the position shownin diagram C. In this construction thepiston is normally pressed to the right by the spring 9 and the valves10 mounted on the rod V11 secured to the cylinder head controls the liowto the oppo site sidesof the piston, .the direction of `flow beingindicated by the arrows.

In the diagrammatic illustration of F ig'. 3, the water actuated memberis in the form of a diaphragm 52 which is moved 'up to the positionshown in diagram B when cold water is first turned on, the flow beingfrom v inlet 12 to the outlet 62 via ports 12 and 153 `thetherinostatically as indicated hy the arrows, and is moved down to theposition shown in diagram C ,when the valve .32 has been shifted to theposition shown i-n'that diagram by the heatlngeffect of the iiowingwater, the How from the inlet to the outlet then being via the ports 1-1and 15. As before, the movement of the water actuated member to theposition of diagrani opens the gas valve, and the movement of saiddiaphragm to the position shown in diagram C closes the gas valve.

In the diagrammatic illustration of Fig. 4:, the water actuated memberoperated bydiiferential pressure', the chambers on the two sides of thedial'ihragm being connected to two oints X and Y of different,potentialin the owing stream of water. In this case controlled Vvalve 33operates, when in the position shown in diagram B, to connect thechamber ont-lie lower side of the diaphragm 53 with the point. Yof-lower potential (via passages 16, 17

and 18), and the chamber on the upper side.

of the.4 diaphragm `with the point X of higher ,potential (viapassages19 'and 20). This results in' a depression of the diaphragm and with itof the'gas'i'falvea., thus allowing fuel to iiow to z the main burn"-ers of the heater.4 When the water has `been heated to a point at whichthe there mosti-ttv is set to act, lthe latter:- i'noves .the

valve 33 to the position shown in diagram C, and in this position theconnections to. the chambers .on the two 'sides' ofthe diaphragm arereve reed, the point X being oonnected to the lo er side of thediaphragm via the passage 21 and the point Y being connected to theupper side of the diaphragm Nia the passage 22, and the diaphragm isforced upward closing the gaS valve 73. y i l Referring to the generalarrangement of parte shown in Figs. 5 and 6, which figures illustratethe ordinary type of water heater with my improvement applied thereto; Dthe easing of'the heater; E, `Fand G are the upper coils; H isf-thellower reverse coil of the heater connected to the upper coils by meansof lthe pipe I; K'are the burners mounted upon the usual burner ring; Lis the gas supply'pipe; M is the easing of the valve for controlling thevsupply of Igas to the burners; N is the pipe leading from the easing'of the gas valve to the burner ring; 0 is the thermostat casing; and Pis the vcasing containing the water actuated member, the casings O vandl being shown in enlarged cross section in Fig. 7.

Referring now to Fig. 7 in connection with Figs. 5 and 6, 31 is the coldwater inlet by means oi which water is supplied to the heater from themain, and this pipe communicates' with the chamber 32 in which islocated the thermostatically waterelowv valve 33 which corresponds infunction to the valve 3 heretofore referred to in the diagrammaticapparatus of Fig. 1.

' This valve E33 is provided -wit-h two heads 34 and 35 which areadaptedto engage respeetively with the seats 36 and 37.v When the valveis inthe position shown in the figure with the head 35 in engagementwith the seat 37, the water flowing into the chamber 3'2- passestherefrom through the port 38 tor'th'e left hand end of t-he cylinder39, containing the wateraetuat'ed member 40. lNhen the valve ismoved tothe left so that the head 34 enga-ges with the Seat 3G, the waterflowing into the chamber 32 passes through the' port 41 to the righthand end of the cylinder 39. On the side of the cylinder opposite to theports 38 and 41 there is provided an out-lctport 42 so located that whenthe piston 4;() is in its normal left hand position., the front edge ofvthe poit42. is in communication with t-hc'right handend of the cylinder39, The port 4:2 opens into a chamber which containsa slining'supportedand balanced ball check valve 43, that will.

controlled loo permit the Water to flow from the port 42 tothe inlet 43"of the upper coil E` (Fig.

,5), but will prevent any flow of'liquid in inder 39 there is a smallervcylinder 47, and 13o Working in this cylinder is a'plunger -48 Which isprovided at the left hand end with a lliead 49 engaging With theadjacent portion of the Water actuated member 40. A pipe 50 leadsfromthe middle of the thermostat chamber to a port communicating with theright'hand end of the cylinder 47. A4

r are provided w1th compression-springs numbered .respectively 56 `and57, and the parts 40 and 48 are arranged so that `vvhen they have beenmoved by the spring 56 to the eXtreme left hand position as determinedby the engagement of the pist-on head of the plunger 48 With theshouldt-u'edl end of the cylinder 47the port opening 55 will beuncovered and Water can pass'from the thermostat chamberthrough thecylinder 47 and thence to the inlet 43rl of the heater coil. Lo-

" cated 'in the chamber 45 is a composite vthermostat member of theusual construction comprising an outer expansiblev tube 58 of copper,brass, or z1nc,and an inner'negative element 59 of porcelain,nickel,`steel or invar metal. lThe outer element 58 is secured at itsupper end to the wall of thetherrnostat l chamber, and 'is in abuttingengagement at its lower end with the negative element 59.-

T he latter terminates at its upper end in a .knife'edge 60 whichcontacts with the shortI arm of tie multiplying lever 61. ,The long armVof this. lever envages with an adjustable nut 62 on the end ofb thestein 63 Which actuates the Water loW valve 33.V The lever 61 is kept inoperative engagement with its cooperating parts by means of a tension.spring 64, and the stem 63 is also provided ivith an adjustable washer65 engaging a compres.

sion spring 66 surrounding the stem 63. The relative strengths 0f thesprings 64 and 66 are about as two to one so that when the lever 6]. isbrought into engagement with the nut 62-'-by the expansion of thecomposite thermostat and '..the consequent retraction of the knife edge(S0-the pull of the spring G4 Willovercome the resistance'of thecompression spring 66 and move the valve over to the left until the head34 engages With the seat 36 and closes the openi'n to the left' handendof the/.cylinder 39. -hen the lever 61 is moved t0 the right-by the.contraction of the thermostat and the consequent lifting of the' knifeedge (iO-until it is out of engagement with the nut 62, the spring 6GWill move the valve 33k to the right to the position shown. in thefigure. The operation of this mechanism is as follows: When .no water isovving through Vbe drawn away from the the heater, and the parts arecold, the valve will, as already stated, occupl tion indicated in thedrawing. hen a fioW of lWater is started-as by opening the house tapconnected with the pifpe 46+vtater will ront of the piston 40 throughthe pipe 50 and the tvvo ports 42 and 55 thus reducing the pressure olithe right hand side of sald piston and 'allowing 1t to bemoved forwardby the ressure of the water lowin in through t e port 38. As the pistonadvances it carries with it the plunger 48 and closes oli' the openingto the port 55 but Water will still continue to be drawn from in frontof it through the port 42, and the'piston 40 will continue to advanceagainst the pressure of the springs 56 and 57 until it reaches theposition indicated-in dotted lines, or until the left hand side of theport 42 has been opened to allow the direct flow of water from the coldWater supply p1pe31 through the port 38 to the house in let As thepiston 40 advances, the end of its stem 5l engages with the end of thegas valve stem 53 and raises the gas valve 54 from its seat allowing thefuel to flow from the supply pipe L' to the lfeed pipe ,N which leads tothe main burners of the heater. 'd The piston 40 will remain as long asthe valve 33 occupies the position shown in the figure and watercontinues to flow through the port 38. But, when .the

the posiin its forward position i temperature of the .flowing liquid .inthe thermostat chamber 45 rises above a certain point the expansion ofthe positive elementV 58 and the consequent retraction of the knife edgeGO. allows the thermostat lever 61 to be i drawn intoeugagement with thenut 62 on the stem ofthe valve 33 andivhen this occurs the said valvewill befinoved' to the left, closing the openingo'i. the port 38 andopen` ing that of the port 41. The flowing Water will now pass from thecold Water supply pipe to the front ot' the piston 40 and will force thelatter back until the front edge of the port42 is opened flow directlythrough that port to the inlet 43,, The retraction of the piston 4Q andwith it the stein 51 allows the gas valve 54 to be closed by thepressure of itsspring'57, thus shutting off the supply of fuel 'to themain burners. As the temperature in the thermostat chamber falls, thecontraction of the positive element 58 Will lift the Vknife edge 60 andmove the lever '61 out" of en gagement with the nut 62, whereupon thevalve33 will be moved to the` rightby the spring 6.6, thus closing theopening ,to the poi't 41 and again opening that to lthe port 38. Thepressure of thelowing Water will 4then move the piston 40 again toitsforward position, thereby once more opening the gas valve 54. Thesealternate'opem ing and closing increments will tontinue with eachcorresponding fall and rise of the so that Water can i `cylinder 39.

`temperature of the flowin the llow of water is shut' o the pressure ofthe liquid on the two sides of the water actuated member 40 is at onceequalizcd and the latter will normally be returned to its left handposition by the joint pressures of the springs 5G and 57. It, for anyreason, any of the valve par-ts should stick and the spring pressuresshould be insuilicient to overcomethis sticking, the valve will beforced back to its 'normal left hand posi tion 'by the continued heatingof the water in the coils in the following manner: As soon thc-llowofwater stops, the ball. check valve/43 will return to its seat and closeoli' communication ybetvv'eeirthe cold Water inlet 43a and the left handend of the The closing of the outlet in the house supply `pipe 16 alsoconfines the liquid on the outlet side ofthe heater, and the pressure'generated in its confined body of liquid by the continued heatingeffect of the main burners will be communicated through the pipe 50 tothe cylinder 47 and will act to forcethe plunger 48 and with it themember 40 back until the port opening 55 has been uncovered. Before thisoccurs, the'gas valyc 54 will hare returned to its seat, thus cuttin oilthe fuel supply to the main burners; he opening of the port 55 allowsthe water to circulate freely through the coils vof the heater under theinfluence veo of the heat of the pilot light.

The uncovering of this portate-ach return of the water actuated memberto its normal left hand' position when the water is flowing also allowsa small amount of cold water to ilow from the. portl opening 42 throughthe port 55 and ipe 50 to the thermostat chamber '45, an this aids inmore rapidly .reducing the temperature in vsaid chamber to the pointwhere the thermostat will act to -operate the water supply valve 33 andthereby again open the gas valve 54 in the manner previously-described.This mixing of a small amount of cold water with the out-flowing hotwater from thc heater aids me in reducing or eliminating valve '72, anda watt'fr inlet connection 73 connected to the upper end of the heatingcoil or receptacle. After passing through l this coil or receptacle, theWater emerges from an outlet connection 7 4 which commir iiica'tes withthe Lower .end of the thermostat chamber 75. This thermostat chambercontains a thermostat which` inA this caseyis liquid. When 'shown inFig. 1.

constructed of a nest of nickel steel or invar metal pipes, 76, 77, 7 8,screwed attheir lower ends into a head 79 and brazed at their upper endsto a head 80 which carries a flexible diaphragm or corrugated member 81.The pipes 76, 77 and 78, the heads 79 and 80, and the corrugated'boxdiaphragm 81 are lilled with somev liquid having, a high coefficient ofexpansion such as petroleum oil, or parallin, and the head 79 isprovided with a tightly fitting screw 82 and a flexible washer and locknut 83 by means of which the internal volume of the'thermosl'at membermay be varied. The corrugated diaphragnrmember 81 is capped Aby a platecarrying a knife edge 84 which engages nected to the center of thedouble headed supply valve 89 which is similar in construction to thecorresponding valve 33 The two heads of this valve 89 are adapted toengage respectively with the valve seats 90 and 91 and thereby controlthe alternate flow of water through the, ports 92 and 93. These portslead to the upper and lower ends of a chamber 94: which containsl thewater actuated element- In this construction this element 95 1s made 1nthe form of a. puppet valve engaging with the'sea-ts 96 and 96a. Thestem 97 is secured to the valve 95 and leads downward tlnough anauxiliary chamber 98 an'd a stuing box 99 to the gas valve stem 100.`The stem passes through the front wall ol the gas valve chamber 101 andis secured to the gas valve 102. The latter proi-idcd at its bach with aboss carrying a leather washer 103 which, when the. gas valve is open,is seated against the 'front wall of the gas valve chamber therebypreventing any leakage of gas around the stem and eliminating thenecessity for a stutliug box. The

gas valve 102 and the water actuated memer 95 connect-ed thereto arenormally kept 1n their seated position by means of a compression spring108 interposed between `the gas valve 32 and the opposing headof the gasvalve chamber. The gas valvemay be placed at any distance from the wateractuated member, since the connecting stems 9T and 100 are always undertension, 'and may thereforebe` made of any length-even though of verysmall dia1net`e1'f-witho\1t danger of buckling or other distortion. Anauxiliary water valve 104 is engaged by a head vvon the stem 97 in sucha posit-ion that .when the water actuated member 95 is raised to openthe gas valve 102, the valve 104 will be seated by its spring andcloseoli the oper ing between-the chamber 98 and the chamber 94. A small pipe105 leads from the chamber 98 to the cold water supply pipe in front ofthe check valve 72. An outlet 107 leads from the center of the chamber9-1 to the house supply system. L is the inlet to the gas valve chamberand N is the outlet leadingto the burners.

The operation of this control apparatus is as follows: Then the partsare cold, the contraction of the liquid in the thermostat chamberrctracts the knife edge 811 and allows the valve '89 to be lifted to theposition shown in the iiguref thereby opening the port 93 and closingthe'port 92. 'Vhen the flow of liquid is` started-as by opening a 'ifaucet connected with the house supply' pipe pressure of the waterflowing throng the l107- water is Withdrawn from the upper part of thechamber 94, thereby decreasing the pressure on the top .of the member95, and the latter islifted away from its' seat 96 and forced againstthe seat 96a b the port 93. The lifting of the member 95 closes theport'leading to the chamber 98,

thereby compelling all ofthe water which i passes `through the port 93to iiow to the discharge pipe 107. The upward movement V4of the member95 likewise lifts the gas Valve 102 away from its seat allowing the fuelto "'-flow `fromy the supply pipevL through the valve chamberuto thefeed pipe N which leads to the i'ain burners .of the heater,

where .it is i ite'dby the flame of an ordinary pilot hght'sup liedthrough a separate pipeV (not Shown 'When the temperature of the water-'ilowing through the chamber '75 has been 'raised to a predeterminedpoint the expansin of the liquid in said thermostat will lift the arm 85and the screw 86 out of contact with the thermostat lever 87 and thevalve`89. Will thereupon be depressed by the pressure of the spring 112'thus closing the opening to the port 93 .an

opening that to the port 92. The water will now flow directly from thechamber 88 to the upper part of the chamber 94 and the -valve member 95will be pressed away from the seat 90* and down upon its seat 96, bothby the pressure of the flowing water on its upper surface, and by4 .theaction. of the spring 108.V This seating of the member 95 allows the gasvalve' 102 to ,close-'fand thereby cuts oi the {iow of fuel to` the mainburners of the heater. The subsequent lowering of'the temperature of theliquid 1n the thermostat chamber permits the arm 85 and screw 86 to oncemore engage the short -arm `of thel thermostat lever 87 and the pressureof the springs 113 and 114 acti-ng upon' the arm lifts the valve S9,closesthe,A opening to the port 92 and opens that tov The owing waterwill then the port 93. once more act upon the lower side ot'the member95 to lift it from' its seat and 4si--v multaneously open the gas valve102.4 When the flow of water is entirely shut oli', the pressures on thetwo sides of the valve member 95 will be at once equalized and the valvemember will be returnedto its scat by the pressure of the spring 108. Asthe valve stems 97 and 100 can in lthis construction be made yofveryfsmall size-as they are under tension only-and as the constructionalso permits of dispensing with astuiiing box for the stem 100, thereisvery little possibility of any of the valve parts sticking so as tohold the gas valve when the water has been shut oif. But if suchsticking should occur, the valve member 95 will be forced downto itsseat 96 uponthe subsequent heating and expansion of the liquid intheheating 4receptacle in thefollowing manner: men the How. of water stops,the check valve 72 returns to its seaty stat normally shuts oli the gas,the heating of the Water in the coils will first of all actuate thethermostatic mechanism to open the passage to the port 92 and close thatto,

. ture is less than that at which the ther-mo i the port 93. AAs theopening from the chamf l ber 98 is also closed by the valve 107, the

l entire pressure produced by the further heating of the inclosed bodyof liquid. will .then

be exerted on the top 0f the valve member 95 and will force-it down toits lower seat 96. The forcingdown of the valve member 95 immediatelycloses the gas valve 102 and prevents any further heating of theinclosed liquid.

When the valve 95 1s ixrits seated' position,

the opening of the port between the chamber 98 and the chamber 94establishes an open -circulating connection between the two ends, 73 and74, of the-heater coil and allows the contained liquid to circulatetherein under the influence of' the heat of the'pilot light. f In Fig.9, 121 indicates the cold water supply ,pipe leadingvtog the chamber 122inl which is located the thermostatieally controlled water diverting.valve As in the previous constructions, this valve has two heads 123and 124 adapted to engage' respectively with corresponding seats so asto close the openings tothe ports 125 and 126 which lead into the upperand lower ends of the cylinder 127 containing the water actuated pistonmember 128. The piston 128 is bored at its center to rfceive the hollowstem 129 which' parses loosely through the cap 13 0 and is secifredwater tight therein by the use 0f rubber gaskets 132 and 133 and a cap134.

3() v movement at all when the flow of water is valvehthroughtheengagement of the end of thc stem 414.2V with the end of the Stem' 144thus alternately starting and stopping the flow of fuel to the mainburners or the heater. When the flow of water is stopped, the partswilljbe returned to their normal position bythe action' of tliesprings'161 and 162, ilnlessksonie sticking should occur; vIn such case-theparts will be forced back 'to normal position bythe continued heatingand expansionfof the inclosed body of water in the heater in the samemanner as previously explained in connection with the description `o theconstruction of Figs. 7 and 8. Thus on shutting o the tap in the housesupply system and stopping the How of water the ball valve 137 willautomatically return to its scat, and pressure generated in the liquidin the heater coils by any continued heating of the same will becommunicated through the port-160 to the upper side of the plunger 139andwill force the latter, together with the piston 128, back to its nor-'maldepresscd position. `Whenrthis has' 0ccurred, the port'opening 160will' provide for a continued circu ation of the water through the portsfrom the inlet to the outlet side. In order to facilitate the movementofthe piston member 128 at the. vextremes of itsI travel, and inorder'also to prevent any less l,than a.; certain amount, I providesmall leakage ports 163,163, which allow a certain small-amount'ofliquid to 'pass -directly from In lthe construction shown'in Fig. 10,171

the y*Side of the'piston member to the other.

' indicates the cold water supply pipe leading into the chamber in whichis located the thermostatically controlled water directing valve 172. Asin previous cases, this vabe is` provided with two heads adapted toclose the openings to the two ports 173 and 174 communicatingrespectively 'with the upper and lower ends of the cylinder 175 whichcontains the Water actuated piston. member 176.l An outlet 177 leadsfrom the upper endof the cylinder 175 to the inlet 178 of theheatingcoil or heatinrr receptacle. The water actuated member 176 is bored atits lower end to receive the conical plunger 179 which is held in thehead "180 by means of s, spring 181 `and a nut 182. The stem183 issecuredto` the Water actuated member 176.

justabove the end of the conical plug valve 179, passes d own throughthe latter and through astulling box 184` in the end of the head 180 andengages by means of ai fork 185 with' the stem 186 of the gas valve 187.

4 The water actuated member 176 is further 'provided with a'yalve seat188 upon which rests thevalve 189the latter,being` held lightly onrsaidseat'by means of a weak v springr 190 interposed between the valve 189and the head 191 which is secured to the upper end of the piston 176. Asecondstem the 4house 192 which` passes freely through the center ofthe' head 191 and carries a valve 193 ,i

which is adapted to .el leading from the upper end of thecyhnder 1 75into a chamber 195, and this chamber communicates in turn through asmall port ose a port opening 194 opening 196 with the chamber containiua I thermostat 19S which controls the position of the water directingvalve 172. .The inlet 178 communicates with the `upper end of i aheatingchamber of any desired formpreferably a coil of copper pipe-andthe' water after passing through this receptacle emerges through a. pipe199- which enters.

the lower'end lof the thermostat chamber 197. An outlet 200 leads fromthe upper part of this 'chamber to the house supply system. Thethermostat in this constructlon consists of a thin disk-shaped hollowchamber which isrfilled with liquid having a high coefficient ofexpansion, and preferably having considerable density 31nd viscosity,such as heavy petroleum oil,n paraffin, mercury or fusible metal whichme ture less tha-n that for which the thermostat is designed. to act.This chamber is provided with a central pipemember 201 containing anaccurately Vfitted piston or lunl'ts at a tempera-- ger 202 whichprojects through the ower head of the thermostat chamber and is inabutting engagement with the upper end of the stem' 203 which passesdown through the water' directing valve 172 and terminates in a head 204bearing upon a compression spring 205 interposed, between said ,headandthe cap 206 which .closes the lower end ofthe chamber containing thewater direc-ting valve 172. A second compressionspring` 207 isinterposed between the upper side 4of said valveY 172 and the oppositeend of the lchamber containing said valve.V The ort the position shownin the figure.

e operatiohof this control apparatus .is as follows: Vhen the water 'inthe apparatus is at a lower temperature than that 'for which thethermostat l's designed to act, the

engagement with the end of the stem 203 and the pressure of the spring205,--which head of the plunger 202 is withdrawh from is about twiccasstrongas' the spring 207 lifts the stein' 203 and with it the waterdirectin'g valve 172 until the upper head of.

said 'valve closes the opening to the port 174. This leaves the portl173 in communication with the iulet'pipe 171. and when a tap in wateris withdrawn from the heater and from the upper ond of the cylinder 175service pipe 200 is opened and.

i through the pening 177 and the port openings 194 an 196, the water[lowing in through the port 173 lifts the piston 176 away from valve 179and allows the water to flow past, this valve to the upper side of thepiston member 176. 'This water lifts the valve 189' from its seatthereby ait'ording a free passageway for the liquid to the inlet 178 ofthe heating receptacle. The lifting of the piston member 176i .trees thehead of the stem' 192 from engagement with the npper'llead 19101 saidpiston and allows the spring 211 to seat the valve 193thus closing theport opening 191 and shut-ting ofi.' the direct flowof water from Itheupper end of the cylinder to the thermostat chamber 197. The liftin'vofthe valve member 176 brings theforkednend 1ST) of the stein 183 intoengagement with the head of the gas valve stem .186, and the continuedupward movement of said piston lifts the gas' valve 187 from its seat,allowing fuel to flow to the gas j valve chamber from the feed pipe L*to the supply pipe N* which communicates with the main burners ot theheater. The lift-ing of this gas valve brings a leather washer on i..its upper side into'engagement with a' boss stuffing box is used.

flowing, the temperature of the discharged .on the inner'side ofthe'hcad through which stem 1 86 passes and thus prevents any leakage ofgas around that stein even though no It', while wat-er is still liquidreaches a point above that forwliich the thermostat is Set it maybe setto act` at any temperature by means of the screw 214) the expansion ofthe liquid in said thermostat chamber forces out the plunger .202 untilit engages with -tlie end of the stem 203 and compresses the spring 205suliiciently to allow the` water directing valve 17)J to be forced downby the spring 207 until the opening to the port 173 is closed and theopening to. the portI 17-1 is opened. The inowin r water will now passthrough the port 1 4 to the upper -side of the piston 176 and thepressure of this water acting in conjunction with the spring210 willforce the piston member 176 back to its lirst position,

'the cold water'now flowing directly through the port 17-1 to'thcopening 177 and thence on to the heating receptacle. The downwardmovement. of the piston 176' frees the fork 185 from engagement. withtliehead of the gas valve stem 186 and allows the/gas valve 187 to beseated by the pressure of its own spring, thus closing off the flow offuel to themain burners. The downward movement of the piston'176likewis'ebriiigs its head 191Qinto engagementwitli the headoftliefivalve1 stein 192fand' opens the poi-t l191,thus lallowing'` asmall:-ainonntvot cold watertollowv difi'ectly'tfro'ni the upperendof:the-cylinder 17? through the portopenings 194 and 196 into thethermostat chamber 197 where it mixes with the iiillowing lifting thcpiston 176, opening the gaS'va-lvey 187, and permitting the closing ofthe valve 193 in the manner already described; This alternate reversalof the flow of cold liquid to the lower and upper sides of the wateractuated member 176, with the vconsequent lifting and depression ot'said member, andthe consequent, opening and closing of the fuel supplyvalve, will continue' as long as the water flows through the heater andis successively cooled or heated below or above the pointat which thetlicrmostatic control is set to act..

When the flowing water is completely shut olf, the piston member 176 isnormally returned to its lowest position-if at that time it was not inthat position--by the l spi-ing 210. But if for any reason the pressureof the spring 210 should be insuilicient to restore tlielpiston member176 to its norinal position--liecause of the stickin of any oftheparts-fthe construction o? the 'apparatus is such that said piston willbe forced down by the continued heatngrof the liquid in the heatingreceptacle in the following manner: As soon as the flow of water stops,the valves 189 and 208 will be seated by their respective springs andthus confine the liquid in the heater between these valves and the bodyof water in the closed,houseahserviee pipe, 200, and as this liody ofwater continues to heat up, it will exert a positive pressure on the topof the 'piston 176 which will ultimately force that piston to the lowestpositioiiand thus insure the closing of the "as valve 187 and thecomplete cutting oti'b of the fuel supply to the main burners. l

ln the lowest position of the piston 176 the port opening 191 is alwaysopen, and

the inlet 178 and the outlet. 199 of the heating receptacle, and insuresa free circula.- i

to the upper Iieatercoil, such-pipe being pro-*videdwithftliezspring-held Vcheck valve222 for giving a difference in'pressure on the` two sides thereof when the outlet from the heater isopened. is a piston working in the cylinder 224 and provided with la.

In this'constructon, 221 is Iso this affords a free communicationbetween stem 225 for pulling the ges vulve (not shown but constructed inthe other forms of invention heretofore described), open when thepressure` on the two sides ofVV the piston 223 is unbalanced und the piston moves to the right. Beneath the ovlinder 221 a. vulve chamber 220provided with u recrprocutory valve 227 having washers 22B-Eind 229adapted to sent against the seats 230 und 231. The vulve is alsoprovided at its ends with the seats 232 and 233 adapted to sent againstthe ivnshers 234- and 235. The vulve is operated from the thermostat bymeans of a stem 231i, the connection beingl such that the vulve is movedto the left when the temperature of the water in the heater rises abovea predetermined point.

The operation, assuming the pertsto be in. the position shown. and theWater in the heater cold, is follows. On opening the outlet from theheater, Water flows into the heuter through the inlet pipe 221. 'Thisflow of water Causes n difference of pressure on the opposite sides ofthe valve 222, the pres sure on the right hand side being less then thaton the left hand side. This difference in pressure is Communicated tothe opposite sides of the piston 223, vie the port 237, passage 241.,chamber 226 and port 238 on the one hund, and the port 239, chamber 226and port 24:0 on the other hund. This differentialpressure on the twosides of the piston moves it to the right, thus opening the gas valve,and permitting u. free fiovv of gus to the burners of the heater. Thisaction will continue as long as the outlet from the heater is open andthe temperature of the water inthe heater is below s predetermined pointfor which the thermostat is set. If the temperature of the water risesabove such point, the thermostatie eontrot ling ineens ceuse'themovement of the stem 236 toA the left. This Causes the sent 232 toengage the Washer 234 and to disengage the seat 233 from the i Yusher235. At the sume time the sont 230 engages the washer 228, and theWasher 229 is disengaged from the Washer 232. This eeets u. reversal ofthe differential pressure on the two sides of the piston 223, as theright hund side of the piston is now connected with `the port 237x vinthe passage 24h passage through the vulve 227, chamber 226 and port 240,while the left hund side of the pistou eonnected with the port 239, vinthe chamber 226 and port 238. Thisreversal of dii'erentiel pressure onthe piston moves it to the left, thus closing the ges vulve, When theoutlet from the'henter is closed with the w i ter cold, the piston 2234assumes the position shown in the figure, by reason of the smell port242 inthe check valve which permits an equalization oi? pressure onopposite sides of the check valve when no Water is flowing.v und allowssaid piston to be moved toV the left by the unbalanced pressure on; thepiston due t0 the stem 225 and by the action of a. supplemental spring244. When in the closed position, the opening around the stem 225 issealed by the engagement of a washer 245 secured to the central boss ofthe pieton 223, with an opposing boss 246 pn the cylinder head. Thisprevents any leakage of liquid from the cylinder when. the heater is notin operation even though the stufling box 247 muy be quite loose Asl thestrain on the stem is solely one of tension seid stem may be made verysmnlll thus reducing to u minimum the friotionel resistance to itsmovement through the stuffing box even when the lutter is uccidentullscrewed. u.

too tightly.

The piston 223 does not have to move over any open ports, sndmuy be`therefore providedivith soft peeking rings 247 which ef fectuellyprevent leakage from one side of the piston vto the other While offeringvery" little resistance to niovement in either cli reetiou.-Fiimllysince no We ter fion's through the cylinder 224, und the onlymovement oi the liquid through the ports 237 end is that required toprovide for the differential displacement of the piston member 223,there is very little opportunity for the deposit of sediment around theworking ps rts or for corrosion of the engaging surfaces. The

movement of the liquid is so small tha-t the port openings 237 and 239may, if desired, be lled with porous filtering plugs which' willefectusllyY prevent the entrance ofony dirt or grit to the vlve undpiston chambers, While interfering not al. ull with such slight movementof the liquid therein asis necessnrv to eiert the required movements ofthe parts. iIt will also be noted that the construction of' the waterdiverting vulve und 'its seats is such that the entire mechanism may bereadily removed und replueelgl by removing the oep 248, und in ease ofweer the vulve seats 231i: und can euch be sepa rutely adjusted byscrewing in or out the plugs on which they :ire mounted.

For ell these reasons the danger oi the Water piston sticking in theopen position is in jthis construction practically eliminated "sind noprovision for forcing it buck to its from the heater when the outletfrom the heater is opened to secure the opening of the gas valve, andmeans actuated by the thermostatic means whereby the pressures in thetwo chambers are interchanged and the gas valve closed when thetemperature of the water rises'above a predetermined point.

2. In a'n automaticwater heater, a burner, a gas valve for controllingthe supply of gas to the burner, a pair of pressure chambers, meansactuated' by differential pressures in the 'chambers for operating thegas valve, communications from the chambers to separated points of theheater having different pressures when the outlet from the heater isopen, thermostatie means operated by the heated water, and meansactuated by the thermostatic means whereby the said communieations arereversed and the pressures in the chambers reversed when the tempera-`ture of the water in the heater rises above a predetermined point.

3. In an automatic water heater, a burner,

a gas valve for controlling the supply of gas to the burner, a membercontrolled by variations 'of water pressure in the heater for openingthegas valve and arranged to receive a given pressure on one side when theoutlet from the heater is opened, thermostatic means governed by theheated water, and means governed thereby for securing a shift of thesaid given' pressure to the other side of the said member, and a closureof the gas valve' when the temperature of the water in the heater risesabove a predetermined point.

4. In an automatic water heater,'a burner, a gas valve for oontrollingthe supply of gas to the burner,. a 'member controlled by variations ofwaterl pressure in the heater arranged to receivea given pressure onone' side to open the gas valve when the outlet from the heater isopened, thermostatic means governed by the heated writer, and a valvegoverned. thereby and arranged t0 shift the said given pressure to theother side of the said member and secure a closure of the gas valve whenthe temperature of the water in the heater rises above a predeterminedpoint. 1 f

5. In an automatic water heater, the combination of a water heatingconduit, a fuel supply valve, a pressure motor for govern ing the fuelvalve, said motor having a reciprocating member therein ydividing saidmotor into two chambers, each being in communication with said conduitwhereby differential water pressures are sustained in said chambers whenwater is being discharged from said conduit, a thermostat governed bythe heated water, and means actuated by the thermostat adapted to interechange said water pressures when the heated water rises above apredetermined degree whereby the fuel supply valve is closed.

6. Ih a water heater, the combination of a valve casing comprising acylinder having an outlet port communicating with the heater, a pistonvalve' in the cylinder movable over said port, water inlet passages tdthe cylinder on opposite sides of said piston, a valve controlling bothof said passages, a thermostat exposed to the water heated in the heaterand operatively conneeted'tothe last mentioned valve, and a gas supplyvalve to the burner of the heater controlled by the movement of saidpiston. f

In testimony whereof signed my name in the presenqe of subscribedwitnesses.

FRANK L. o'. wADsWoRTH.

ther two Witnesses:

LETITIA' A. Mms, DOERING BELLINGER.

I have. fhereuntdA

